Brain Structure and Function in Patients after Metal-on-Metal Hip Resurfacing

Article Figures & Data

Download figure
Open in new tab
Download powerpoint
Fig 1.
Voxel-based morphometric analysis of differences in brain gray matter attenuation between the MoMHR and THA groups before exclusion of patients with primary ocular pathology. Comparative areas of gray matter loss in the MoMHR group are highlighted by using the color bar across the significance value range P < .05 to P < .001 (uncorrected).
Download figure
Open in new tab
Download powerpoint
Fig 2.
Voxel-based morphometric analysis of differences in brain gray matter attenuation between the MoMHR and THA groups, after exclusion of patients with primary ocular pathology. The top panel highlights occipital cortex differences between groups; the bottom panel highlights differences in basal ganglia between groups. Comparative areas of gray matter loss in the MoMHR group are highlighted by using the color bar across the significance value range P < .05 to P < .001 (uncorrected).
Download figure
Open in new tab
Download powerpoint
Fig 3.
Quantitation of brain metal deposition by PRIME R2′ values (second⁻¹). Analyses are MoMHR versus THA by the Wilcoxon test, P > .05 for all comparisons.

Table 1:

Patient characteristics^{^a}

Characteristic	MoMHR (n = 29)	THA (n = 29)	P Value
Age at surgery (yr)	58.9 ± 6.8	59.2 ± 7.5	.87
Sex (M/F)	25:4	25:4	1.00
Time since surgery (yr)	8.0 ± 1.7	7.7 ± 2.5	.51
UPDRS: Part 2 (ADLs) deficit	0 (0–1)	1 (0–2)	.34
UPDRS: Part 3 (motor) deficit	0 (0–1)	0 (0–1)	.76
Whole-blood cobalt (μg/L)	1.72 (1.10–6.01)	0.38 (0.33–0.50)	<.0001
Whole-blood chromium (μg/L)	1.42 (1.01–3.86)	<0.30 (<0.30 to <0.30)	<.0001
Plasma cobalt (μg/L)	1.66 (0.89–4.47)	<0.30 (<0.30 to <0.30)	<.0001
Plasma chromium (μg/L)	2.52 (1.60-.13)	<0.30 (<0.30 to <0.30)	<.0001

Note:—ADL indicates activities of daily living.
↵a Data are mean ± SD or median (interquartile range). Analyses of continuous data are MoMHR versus THA by unpaired t test or the Mann-Whitney U test; analysis of sex distribution is by the Fisher exact test.

Table 2:

Brain volumes^{^a}

Structure (mm³)	MoMHR	THA	P Value
Total brain volume	1.20 × 10⁶ ± 75219	1.18 × 10⁶ ± 96956	.08
Gray matter	5.89 × 10⁵ ± 57984	5.74 × 10⁵ ± 67886	.11
White matter	6.14 × 10⁵ ± 25380	6.01 × 10⁵ ± 34845	.09
Brain stem	22798 ± 2407	22187 ± 2380	.34
Thalamus	14960 ± 989	14710 ± 1086	.36
Caudate nucleus	6544 ± 505	6615 ± 601	.63
Putamen	8512 ± 486	8384 ± 624	.39
Pallidum	3498 ± 339	3518 ± 424	.84
Hippocampus	7026 ± 670	6952 ± 793	.70
Amygdala	2505 ± 289	2342 ± 402	.08
Nucleus accumbens	729 ± 166	715 ± 163	.76